Another senior executive of a Chinese-listed company was drawn into a graft investigation as Shaanxi-based Ginwa Enterprise (Group) Inc, a pharmaceutical company, announced on Monday that its chairman Wu Yijian is "assisting an investigation" at the request of the authorities.

The board of directors of the company, listed on the Shanghai Stock Exchange, stated that trading in its shares would be suspended on Tuesday. It announced Wednesday the resumption of trading starting from Thursday, claiming that the probe did not involve the company. Wu, 55, is also the president of the Ginwa Investment Group, whose business spans several sectors, including pharmaceuticals, transport, hotel, real estate and golf clubs. Heading one of the province's largest private corporations, Wu became the richest man in Shaanxi in 2013 for the first time. Wu is a mentor in Youth Business China (YBC), a national youth start-up education program. Gu Liping, wife of Ling Jihua, former head of the United Front Work Department of the Communist Party of China Central Committee who is under probe, was the first secretary-general of YBC, the Beijing Youth Daily reported. Ling's brother Ling Wancheng also reportedly won a golf tournament in Wu's club in 2005, reported thepaper.cn.